Dermoscopic Evaluation of Scalp Psoriasis and its Relation with Disease Severity: A Cross-sectional Study from South India

ABSTRACT Introduction: Trichoscopy is underutilized in assessing the clinical severity of scalp psoriasis. It might be useful as an important diagnostic and prognostic tool, as it is less time-consuming and more objective than the Psoriasis Scalp Severity Index (PSSI). Objectives: The primary aim of the study was to assess the dermoscopic findings in scalp psoriasis. There was also a secondary aim to relate the dermoscopic findings with clinical severity of the disease, calculated by PSSI. Materials and Methods: This cross-sectional study included 80 patients with scalp psoriasis as cases and 80 age- and sex-matched patients’ bystanders with normal scalp as controls. The scalp was evaluated using a DermLite DL3 Dermoscope with a × 20 magnification and optimal trichoscopic images stored in a computer. Descriptive statistics such as frequency, percentage, and Fisher’s exact test were used for statistical analysis. Results: Among the cases, red dots and red globules were the most predominant finding, seen in 90% of the patients. There was a statistically significant difference ( P < 0.05) in these findings between the cases and controls. Among the 80 controls, pigment pattern and white dots were the predominant findings, seen in 77.5% and 75% of patients, respectively. In patients where dermoscopy demonstrated twisted red loops, the mean PSSI score was 19.8. This difference was found to be statistically significant ( P < 0.05). Conclusion: Based on the above findings, it can be concluded that dermoscopy is a handy, reliable, and noninvasive tool in the diagnosis of scalp psoriasis.